FilterFactory - Function "tan"

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From the manual: Bounded tangent function of x, where x is an integer between -256 and 256, inclusive, and the value returned is an integer between -512 and 512, inclusive (Windows) or -1024 and 1024, inclusive (Mac OS)

Mistake in 3.0.4 documentation: This function is NOT implemented bounded! Unlike cos and sin which are bounded, tan will go off-range.
You can test it with this small test filter:

R = cos(x) > 1024 || cos(x) < -1024 || cos(-x) > 1024 || cos(-x) < -1024 ? 255 : 0
G = tan(x) > 1024 || tan(x) < -1024 || tan(-x) > 1024 || tan(-x) < -1024 ? 255 : 0
B = sin(x) > 1024 || sin(x) < -1024 || sin(-x) > 1024 || sin(-x) < -1024 ? 255 : 0

or more to show only one example (works on Windows and Mac OS):
FilterFactory 3.0.4: tan(-768) == 167772 ? 255 : 0

Click here for a diagram of sin, cos, tan

Syntax

tan(x)

Original Machine Code (in OPER resource) of Filter Factory 3.0 and 3.0.4 for Photoshop/Win32

C++ code

int factory_tan(int parm) {
	int v1 = parm;
	int v2 = v1 < 0 ? -v1 : v1;
	v2 &= 0x3ff; // 1023
	v2 = COS_LOOKUP[v2];
	v1 -= 256;
	if (v1 < 0) v1 = -v1;
	v1 &= 0x3ff; // 1023
	v1 = COS_LOOKUP[v1];
	if (v2 == 0) return 0;
	v1 = v1 << 10; // v1 *= 1024;
	return v1 / v2;
}